Air grabbler
Active Member
What did the Clean Air package consist of on a 1967 Hemi GTX? Would the CAP package be specified on the broadcast sheet? Or did every car receive it after a certain date?
I can’t speak specifically to the ‘67 Hemi, but here is a link to a pretty good article on the Clean Air Package:
https://www.curbsideclassic.com/automotive-histories/automotive-history-chryslers-cap-the-first-effective-exhaust-emission-control/
The system uses a vacuum control valve installed between manifold vacuum, carburetor ported vacuum and the distributor vacuum advance.
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The article states:
“The system comprised this control valve, a carburetor with leaner and more precise calibration, and a distributor with a modified centrifugal advance curve to provide normal levels of spark advance for acceleration and cruising despite the retarded basic timing.”
“Starting in 1966, CAP became standard equipment on all Chrysler Corporation vehicles sold in California, and Chrysler even offered “UCCAP” (Used Car Clean Air Packages) at dealer parts counters, for retrofit to any 1955 or newer Chrysler vehicle.”
Chrysler was able to get the 426 Hemi Exempt from CA emissions for 1966 model year. In 67 all CA cars were CAP.
For hemi it meant the 4324/4325 Carburetors and different distributor along with emission valve for 4 speed cars. The primary difference is leaner idle jet in rear carb, and distributor with 15deg mechanical distributor advance (30 at crank) with 0deg Initial timing. In 1968 all state cars were CAP required.
My CA original 66 Hemi has that black cap on the air cleaner and no nipple on valve cover.Not sure about 67.
I have some literature around here someplace. But best I remember,,, the only thing different on St Hemis was CA sold car had a hose from air cleaner to valve cover breather.
NON CA sold cars just had a cap on the air cleaner nipple and the valve cover breather didnt have a nipple.
NON CA shown for reference.
PS, there is some argument/debate as if this breather is/was chrome, OR black
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